https://phys.org/space-news/planetary-sciences/ en-us Planetary science and exoplanets exploration news stories and features from Phys.org Halley's Comet captures the imagination in a way that few other astronomical objects do. When it last made its approach toward the sun (admittedly when this author, who is now middle-aged, was 1 year old in 1986), humanity responded with a fleet of spacecraft known informally as the "Halley Armada." Yet because of the comet's trajectory, those spacecraft were only able to visit their target for a fleeting few hours, leaving planetary scientists wanting more. Now, a new paper by researchers at Khalifa University and their co-authors, available on the arXiv preprint server, describes a mission plan that would allow a spacecraft to rendezvous with this best-known comet for the first time. https://phys.org/news/2026-09-mission-rendezvous-halley-comet.html Space Exploration Tue, 08 Sep 2026 19:00:05 EDT news708088306 Southwest Research Institute (SwRI) scientists used simulations to understand the role disruptive impacts play on icy moons with subsurface oceans in our solar system. A recent paper published in the journal Nature Astronomy concludes that disruptive impacts can affect the presence and persistence of subsurface oceans in these moons but do not seem to create new oceans. https://phys.org/news/2026-09-giant-impacts-small-icy-moons.html Astrobiology Tue, 08 Sep 2026 15:40:10 EDT news708093484 For the first time, scientists used the combined power of NASA's Hubble and James Webb Space Telescopes to study some of the most far-flung bodies in our solar system, trans-Neptunian objects (TNOs). Some are the smallest and faintest ever directly seen. The researchers unexpectedly found fewer small TNOs than expected and that the colors of these bodies followed the same relationships as those of their larger family members. https://phys.org/news/2026-09-hubble-webb-solar.html Astronomy Tue, 08 Sep 2026 12:05:13 EDT news708087880 UK astronomers have uncovered new clues about the origin of 3I/ATLAS—only the third known object from beyond the solar system ever spotted. In a new paper published in Monthly Notices of the Royal Astronomical Society, researchers reveal that the comet formed in extremely cold conditions, far from any star. https://phys.org/news/2026-09-interstellar-visitor-3iatlas-clues-frozen.html Astronomy Tue, 08 Sep 2026 11:50:01 EDT news708080978 We usually think of auroras as beautiful lights in the night sky. I see them as visible traces of a connection between the sun, Earth's magnetic field and the atmosphere. This led me to an origin-of-life question: Could the planetary structure that produces auroras also have organized chemical reactions on early Earth? https://phys.org/news/2026-09-early-earth-auroral-belts-natural.html Astrobiology Mon, 07 Sep 2026 20:40:04 EDT news707989182 In 1967, a solar storm nearly triggered World War III by jamming early-warning radar systems in the United States, causing U.S. leaders to think the Soviet Union was responsible. Though society averted catastrophe thanks to timely information from solar forecasters, the threat from space weather remains real. https://phys.org/news/2026-09-economic-solar-storms-pose-power.html Planetary Sciences Mon, 07 Sep 2026 11:40:01 EDT news707994751 After an eight-year journey, a spacecraft carrying European and Japanese probes began the monthslong, high-risk approach to Mercury on Thursday to study the sun-scorched planet. https://phys.org/news/2026-09-spacecraft-bound-mercury-tricky.html Planetary Sciences Sat, 05 Sep 2026 06:20:01 EDT news707723332 As the BepiColombo mission prepares to enter the final phase of its journey to Mercury, a series of studies conducted by researchers at the University of Liège and KU Leuven sheds new light on the early stages of the evolution of the planet closest to the sun. Using experimental petrology, the researchers are reconstructing in the laboratory the formation of Mercury's core, the crystallization of its magma ocean and the formation of its mantle. The studies are published in Earth and Planetary Science Letters, Nature Communications and Advances in Geochemistry and Cosmochemistry. https://phys.org/news/2026-09-mercury-graphite-crust-core.html Planetary Sciences Fri, 04 Sep 2026 16:00:01 EDT news707746443 In a new Nature Communications study, researchers developed a universal scaling framework for the strength of granular asteroids, showing that their tensile strength can be predicted from the size and shape of their constituent particles. https://phys.org/news/2026-09-particle-size-asteroid-strength-revealing.html Planetary Sciences Fri, 04 Sep 2026 14:20:06 EDT news707737328 Earth and the Martian moon Phobos dance together in a series of images recently acquired by NASA's Perseverance Mars rover. Earth appears as a point of light in the Martian sky, disappearing behind the crescent of Phobos, the larger of Mars' two moons. https://phys.org/news/2026-09-perseverance-rover-earth-martian-moon.html Planetary Sciences Thu, 03 Sep 2026 16:40:03 EDT news707659861 Venus is one of the solar system's most unusual planets. It may sometimes be called "Earth's twin" because of its similar size and density, but it rotates on its axis in the opposite direction of most planets, has surface temperatures hot enough to melt lead and lacks a moon. https://phys.org/news/2026-09-doesnt-venus-moon.html Planetary Sciences Thu, 03 Sep 2026 13:10:02 EDT news707657547 Two Mercury-bound spacecraft left their mother ship behind on Thursday and headed down the home stretch of their nearly decade-long voyage to the solar system's smallest and closest-to-the-sun planet. https://phys.org/news/2026-09-pair-spacecraft-closer-mercury-decade.html Planetary Sciences Thu, 03 Sep 2026 12:30:02 EDT news707656831 Recent observations with NASA's Hubble Space Telescope have revealed a giant, evolving, 10-sided atmospheric wave encircling Saturn's south pole. This discovery marks the first time a large, regular-sided jet pattern has been observed in the planet's southern hemisphere. The feature appears remarkably similar to Saturn's famous hexagon at its north pole but is also distinctly different, suggesting scientists may be witnessing a new atmospheric phenomenon developing on the iconic gas giant. https://phys.org/news/2026-09-hubble-tracks-decagon-encircling-saturn.html Astronomy Wed, 02 Sep 2026 16:40:07 EDT news707580122 The Cluster mission danced its final dance as Tango reentered the atmosphere Sept. 1 at 11:30:31 p.m. CEST. The end of the Cluster mission in 2024 marked the start of the reentry data-collection campaign. After four targeted reentries, this is now a proven method of safe end-of-life disposal. It also enabled repeated observation of the reentries by a plane full of scientists, creating a unique reentry data set that will improve our understanding of the destructive process and inform the design of safer, more sustainable satellites in the future. https://phys.org/news/2026-09-cluster-reentry-safer-sustainable-satellite.html Space Exploration Wed, 02 Sep 2026 16:00:03 EDT news707579090 High above Earth, thin veils of metallic haze drift through the edge of space. Known as sporadic E layers, these high-altitude "clouds" form from the vaporized dust of burned-up meteors, earning their name from the unpredictable way they emerge and then dissipate. Now, new results from a NASA sounding rocket—a suborbital research rocket—that flew five detectors through one of these layers simultaneously reveal unexpected complexity in the layer for the first time. https://phys.org/news/2026-09-nasa-rocket-multi-radio-disrupting.html Planetary Sciences Wed, 02 Sep 2026 14:20:10 EDT news707570942 Astronomers at Lund University in Sweden have found evidence of exocomets—comets in other solar systems—orbiting a young star similar to our sun. The observations point to a possible mechanism for how water might be transported from the cold outer regions of the planetary system to regions where planets form. https://phys.org/news/2026-09-young-sunlike-reveals-comets-planets.html Astrobiology Wed, 02 Sep 2026 12:20:01 EDT news707564222 When Blue Origin's New Glenn launch vehicle accidentally exploded during a static test fire in May 2026, the explosion generated low frequency soundwaves below the range of human hearing. https://phys.org/news/2026-09-blue-explosion-infrasound.html Space Exploration Wed, 02 Sep 2026 07:40:03 EDT news707543821 Microbes from space have fueled the plots of science fiction mainstays like "Project Hail Mary" and "The Andromeda Strain." But with more space missions launching each year, finding extraterrestrial life in a microbial form is becoming more plausible. What will the response be back here on Earth if—or when—scientists discover extraterrestrial microbes? Will the international policy and security communities be prepared for the fallout? https://phys.org/news/2026-09-space-missions-life-earth-fallout.html Planetary Sciences Tue, 01 Sep 2026 20:40:01 EDT news707483513 New Southwest Research Institute (SwRI) modeling, conducted in collaboration with scientists at the University of Arizona, shows fundamental differences in how the moon may have formed from the giant impact that created the Earth–moon system. The new results used state-of-the-art computational techniques that factor in the material strength of the two colliding planets. These impact simulations could change how researchers understand moon formation and may help constrain the timing of the event. The research is published in The Astrophysical Journal Letters. https://phys.org/news/2026-09-giant-impact-intact-moon-hours.html Planetary Sciences Tue, 01 Sep 2026 18:20:06 EDT news707500981 More than 3 billion miles (4.8 billion kilometers) from Earth, an ancient icy object is slowly awakening. As it drifts inward through the solar system, the frozen body known as Centaur 450P/LONEOS has begun releasing gas and dust—behavior more commonly associated with comets than with centaurs, the small icy objects that typically orbit between Jupiter and Neptune. https://phys.org/news/2026-09-saturn-encounter-distant-centaur-path.html Planetary Sciences Tue, 01 Sep 2026 18:00:04 EDT news707499541 When the ESA Earth observation mission FLEX launches into space on September 15, 2026, as scheduled, it will carry high-precision optical components from Jena, Germany. Researchers at the Fraunhofer Institute for Applied Optics and Precision Engineering IOF have developed and manufactured a silicon-based double-slit assembly as well as two high-precision mirrors for the spectrometer on board the satellite. The spectrometer is designed to detect the fluorescence of plants excited by sunlight from Earth's orbit. The data is expected to provide new insights into the photosynthetic activity, health, and stress levels of vegetation. https://phys.org/news/2026-09-precision-optics-health-visible-space.html Planetary Sciences Tue, 01 Sep 2026 17:00:05 EDT news707487781 What's so special about spotting Phobos crossing in front of the sun? Sure. It's just another image of Phobos crossing the disk of the sun, as seen from the surface of Mars. Like so much of the modern space era, these images, once amazing, are now almost routine. But there's some real science behind tasking the Mars rovers to conduct a little "Martian astronomy." https://phys.org/news/2026-09-martian-astronomy-percy-phobos-eclipse.html Planetary Sciences Tue, 01 Sep 2026 15:20:06 EDT news707482202 Jupiter hosts more than 100 moons, with most attention focused on the four Galilean moons: Io, Europa, Ganymede and Callisto. This is primarily due to their active geology, including Io being the most volcanically active planetary body in the solar system and Europa having a vast subsurface liquid-water ocean beneath its icy crust. However, Jupiter's smaller, lesser-known moons could provide astronomers with key insights into the history of the solar system because they have remained largely unchanged, unlike the Galilean moons. https://phys.org/news/2026-08-esa-juice-probe-dark-jovian.html Space Exploration Mon, 31 Aug 2026 17:40:05 EDT news707400639 While astronomers have found thousands of exoplanets over the last few decades, the true prize continues to elude them—they have yet to find an Earth-mass, rocky planet orbiting in the habitable zone of a sun-like star. That's partially due to cosmic geography—around half of all sun-like stars near us aren't alone. They have one or more companion stars that complicate their orbital dynamics, as well as those of any planets they might host. https://phys.org/news/2026-08-earth-binary.html Planetary Sciences Mon, 31 Aug 2026 17:20:01 EDT news707400395 When exploring solar system bodies for signs of past or present life, scientists have mainly focused on planets that have (or had) a liquid surface similar to Earth's. However, mounting evidence suggests that the ingredients for life may exist in a very different environment: the highly acidic clouds that blanket Venus. https://phys.org/news/2026-08-peptides-harsh-venus-conditions.html Astrobiology Mon, 31 Aug 2026 15:00:10 EDT news707388361 A Southwest Research Institute (SwRI) study of data from the European Space Agency's (ESA) Solar Orbiter gives the most detailed view of the heliospheric current sheet (HCS) to date. The HCS is a sprawling, undulating surface emanating from the sun to beyond the solar system that serves as the boundary between the sun's north and south magnetic field hemispheres. https://phys.org/news/2026-08-solar-orbiter-ion-magnetic-boundary.html Astronomy Mon, 31 Aug 2026 12:40:04 EDT news707393821 Welcome back to our series on Interstellar Travel, where we look at the many proposals made for sending missions to the stars since the dawn of the Space Age. In our first installment, we examined how Cold War-era developments in nuclear weapons and rockets paralleled advances in space exploration, resulting in proposals for nuclear rockets. We then examined how the creation of thermonuclear weapons led to applications in fusion propulsion. https://phys.org/news/2026-08-interstellar-warp-wormholes-halo.html Planetary Sciences Mon, 31 Aug 2026 11:40:04 EDT news707391962 NASA's newest crown jewel blasted off Sunday to hunt for planets around other stars, explore secret dark energy and survey the cosmos like never before. https://phys.org/news/2026-08-nasa-roman-space-telescope-quest.html Astronomy Sun, 30 Aug 2026 11:26:54 EDT news707307976 Researchers from Tokyo Metropolitan University have created a new system to test magnetohydrodynamic aerobraking for spacecraft reentering the atmosphere. Their platform generates intense magnetic fields with a powerful electromagnet as a miniature vessel is hit with a shock wave traveling at over seven kilometers per second (4.3 miles per second). The magnets reached far higher fields than previous work with permanent magnets and are a crucial stepping stone toward tests with real vessels in the atmosphere. https://phys.org/news/2026-08-method-magnet-powered-safer-reusable.html Planetary Sciences Sun, 30 Aug 2026 11:22:20 EDT news707307711 Some of the strangest weather in the solar system doesn't happen on Earth or even in Jupiter's Great Red Spot—it happens in the interiors of ice giants like Neptune and Uranus. Specifically, scientists have long believed that, at certain pressures and temperatures, it literally rains diamonds inside these planets. For the first time, scientists have mimicked the process they believe creates this phenomenon. https://phys.org/news/2026-08-scientists-diamond-secret-ice-giants.html Planetary Sciences Sat, 29 Aug 2026 20:30:04 EDT news707038082